多种应力路径条件下上海粉细砂的室内试验

Laboratory Experimental Study on Shanghai Fine Sand Along Different Stress Paths

摘要:

通过多组排水条件下不同应力路径的平面应变压缩试验对上海粉细砂的变形强度特性进行了研究,试验结果表明:上海粉细砂的剪应变、体应变、塑性剪应变、塑性体应变、塑性功受应力路径的影响都比较明显,不能作为合适的硬化参数.根据多应力路径平面应变压缩试验结果提出了与应力路径不相关的修正塑性功参量及上海粉细砂本构模型的剪切硬化函数.

Abstract:

The deformation and strength behaviour of Shanghai fine sand is studied through a series of plane strain compression (PSC) tests with different stress paths.The result from the PSC tests shows that the shear strain,volumetric strain,plastic shear strain,plastic volumetric strain and plastic work are all influenced by stress path for Shanghai fine sand.Therefore,none of the above quantities can be used as appropriate hardening parameter for Shanghai fine sand.Based on the experimental results from the PSC tests for Shanghai fine sand,a modified plastic work parameter and the related function are proposed.The proposed parameter and function are independent of stress path,which can be used as the shear hardening state parameter and hardening function in the constitutive modelling for Shanghai fine sand. Key words： Shanghai fine sand; plane strain compression tests; stresspath; hardening parameter; hardening function